Rhythm and timing are the most important factors for a good golf club swing. In order to realize a desirable swinging rhythm and timing, a golfer must master both mental and technical control of the swing. The pattern of such rhythm and timing, however, varies from one person to the other depending on age, physical build, faculty, kidney and other matters, and can never be judged with a certainty. Many theoretical faults on swings in actual play are noted and most of such faults have a direct relation to rhythm and timing. For instance, it is noted that a short and quick swing which is often committed by unskilled golfers can result in "hitting from the top" (which is a fatal defect for golf swinging). As a remedy for this, it has been suggested to delay the impact timing. It is also said that the excessive difference between "whiffing" and actual ball-hitting swings result from the loss of technical control of the swing due to "mental yoke" on the golfer. As a solution to this problem swinging the club always with constant timing is advised.
Although most golfers can well understand these hints as "knowhow", they find it extremely difficult to translate them into action, and therefore appropriate training methods and correcting tools or implements suited therefor are acutely sought. Heretofore various types of effective implements attached to the club shaft or head for practice of swings have been proposed. However, no simple implement designed exclusively for measuring the rhythm and timing of swing is available.